AB1856 IDENTIFYING THE ADULT-ONSET FAMILIAL COLD-ASSOCIATED AUTOINFLAMMATORY SYNDROME TYPE 2
Authors: N. Garvin Grande, C. Zamora Ramos, P. Turiel, E. Álvarez, P. Collado
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Autoinflammatory syndromes encompass a group of diseases caused by dysregulation of the innate immune system that classically present with periodic fevers and usually debut in childhood. <h3>Objectives</h3> An unusual case of an autoinflammatory syndrome with adult onset is presented. <h3>Methods:</h3> <h3>Results</h3> This is a 57-year-old adult woman, ex-smoker, and ex-alcoholic, with no other personal history of interest. She was referred to internal medicine in 2017 for weight loss of 10-15 kg for two months, without other symptoms. Complementary test ruled out autoimmune aetiology and viral infections (hepatotropic and HIV), and a thoracoabdominal-pelvic CT scan identified micronodular millimetric liver lesions and sclerosing lesions in the vertebral and in the iliopubic bones, with no pathological data in a subsequent bone scan. The follow-up showed new symptoms, such as Raynaud's phenomenon, right carpitis (calcium pyrophosphate crystals in synovial fluid), and once again weight loss, and episodes of profuse sweating, predominantly in the evening, without thermometric fever. Studies at that time highlighted massive splenomegaly, retroperitoneal and mesenteric lymphadenopathy. Serologies HBV, HCV, HIV, Leishmaniasis, Rose Bengal, LUES and Mantoux were negative. Acute phase reactants changed from normal to sustained elevation: erythrocyte sedimentation rate (ESR) up to 120 mm/h, C-reactive protein (CRP) up to 136 mg/L and ferritin to 1380 ng/ml. In addition, she began to present progressive cytopenia (red and white series), with normocellular bone marrow biopsy. Given the suspicion of probable tumour origin, a liver biopsy was indicated, splenectomy with excision of abdominal lymphadenopathy with corresponding anatomopathological studies that ruled out tumours such as splenic lymphoma, tricholeukaemia and lymphoproliferative syndromes. After splenectomy, she presented clinical improvement interrupted by febrile episodes lasting a week with self-limited peaks (4-5 hours/day). Coinciding with one of the episodes, she presented with diffuse abdominal pain, vomiting and diarrhoea for which she was admitted. Gastrointestinal examination revealed evidence of hypertensive gastropathy and oesophageal varices, as well as liver fibrosis grade F4 (possible enolic origin). In the current year, an urticarial rash appeared on her legs, arms, trunk, and face, with a biopsy compatible with vasculitis-urticaria, which required treatment (prednisone 30 mg/day and colchicine 0.5 mg/day) getting remission but maintaining the febrile peaks and elevated ESR y CRP. A next-generation sequencing (NGS) genetic study was requested, which detected a c.753C&gt;G p. (Asn251Lys) variant in the NLRP12 gene, a missense-type change. This mutation is associated with familial cold-associated autoinflammatory syndrome type 2. <h3>Conclusion</h3> Although the diagnosis of autoinflammatory syndrome is strongly linked to paediatric age, we should not forget to include this diagnosis in the study of an adult patient with recurrent febrile episodes after ruling out infectious processes before performing invasive techniques. <h3>REFERENCES:</h3> NIL. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.